Few can speak with as much authority on the topic of environmental success as Susan Solomon.
An MIT professor of atmospheric chemistry and climate science, Solomon was the first to identify the chemical process that causes the ozone hole, and she made some of the first measurements in Antarctica demonstrating that chlorine-containing chemicals that used to be in refrigerators and spray cans are the cause of ozone depletion.
In a Sept. 13 talk, Solomon used the phasing out of these chemicals, known as chlorofluorocarbons (CFCs), as well as the phasing out of lead in indoor paint and gasoline, as successful examples from which the world could learn how to meet today's most critical global challenge: climate change.
- Video: Watch the event
CFCs and lead were phased out mainly because of the clear evidence of their danger and strong public understanding of personal health impacts, explained Solomon, who came to MIT last year from the U.S. National Oceanic and Atmospheric Administration and the University of Colorado.
In the case of CFCs, the real reason they were able to be phased out "was because of us," Solomon said.
"Most of these CFCs came from spray cans everyone was using for hairspray and deodorant, so one of the primary sources was literally in your medicine cabinet at home."
When two chemists found that CFCs might deplete the ozone layer and increase risks of skin cancer, "that was enough to get people concerned … [and] it wasn't that difficult to make the change. All you had to do was 'get on the stick,'" Solomon said, parodying a well-known advertisement from that era.
"The key thing that this did was take something that had been very good business and turn it into bad business," Solomon said. To meet the shifting consumer demand, "technological successes were achieved in sector after sector where chlorofluorocarbons were used."
Public understanding and action spurred the technological advancements that paved the way to success. But gaining that broad public support isn't always easy.
In the case of lead, the trail of scientific evidence warning of health impacts went back as far as the Roman Empire, and perhaps even further. Yet it took many centuries before real action was taken.
"One of the reasons we were slow in doing something about lead was because of scientists who were skeptics," Solomon said, displaying a clear parallel to the climate change issue.
In the end, it was civil rights that spurred public engagement, as poor African American children living in deteriorating housing and near highways were found to have higher levels of lead in their blood, Solomon said.
Solomon also pointed out that the developed world had the infrastructure and institutions to make these changes possible.
"It's easy to knock the EPA these days, but the EPA, FDA, Consumer Product Safety Commission, those are all organizations that we have to thank."
Today's environmental challenge: climate change
Many of the underlying health and human rights concerns from the past are alive today, as the world confronts climate change.
The ethical dimension is especially disturbing, and it's making the problem even more complex and difficult to address. Solomon explained that the average person in the developed world emits a 1,000 times more emissions than the average person in Chad, 200 times more than those in Ethiopia, 80 times more than those in Kenya, and 20 times more than those in India.
"Six billion live in the developing world and they emit about five times less CO2 per person than the one billion of us in the developed world," Solomon said.
At the same time, those countries want to grow and develop. If they choose to grow using fossil fuels like the developed world, global emissions will go up significantly.
"So the key question, the key sustainability issue is, what about those peoples' future?" she said. "Should China pay more to develop than we did? Should Africa?
Such questions aren't sparking the same level of public engagement the world saw before phasing out lead and CFCs, but Solomon thinks they should.
"We're in the developed world, we have air conditioning, we have comfortable lives, we have to think beyond us."
While Solomon notes that she personally takes the bus and does what she can to reduce the amount she emits, she's not fooling herself into believing that such actions from everyone will be enough.
"This issue will not be solved by giving up your spray deodorant, this issue won't be solved by taking the bus," Solomon says. "The problem is much bigger."
With no one silver bullet on the horizon, Solomon says research on many different approaches is critical. That could include research on reducing deforestation, increasing wind and solar power, using more efficient cars and building techniques, expanding nuclear, gas and biofuel energy, or employing carbon capture and storage techniques.
To gain this fundamental research and development will require a "bottoms-up technology policy where we start as consumers saying we need a space race for energy technology," Solomon says. "That's what I think we need because engineering and technology has to pave the way. That's why I'm at MIT."